Valve for sealex



March 17, 1959 w. A. BRENNECK VALVE FOR SEALEX Filed June 29, 1955 2 Sheets-Sheet 1 Filed June 29, 1955 2 sheets-sheet 2 l-II 14/ i I 145 INVENTOR. 145 t l 150 W. fr. E/wvfc/f 1'111 5 BY f* W J1 @m91 We EY.

Unite trates VALVE FOR SEALEX William A. Brenneck, West Caldwell, N. J., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application June 29, 1955, Serial No. 518,846

8 Claims. (Cl. 141-65) The present invention relates to conveyor type exhaust machines for the manufacture of incandescent lamps and, more particularly, to a novel valve arrangement for such a machine.

Heretofore, conventional exhaust machines have Vemployed a generally circular turret. conveyor or carrier indexable through a plurality of work stations in a generally circular path. This limitation to the configuration of the exhaust machine is due to the geometry (i. e. the generally circular form) of the rotary valves employed in such machines. Such conventional exhaust valves may be found in U. S. Patent No. 2,113,798 issued April 12, 1938, to Daniel Mullan, entitled Exhaust Valve for Lamp Making Machines and in U. S. Patent No. 2,254,905 issued September 2, 1941 also to Daniel Mullan, entitled Exhaust Machine and Method of Protecting Exhaust Systems, both patents assigned to the same assignee as the present application.

The present objective of the incandescent lamp industry is higher speed production by automatic means or machines. To achieve this higher production it is believed that a straight line conveyor type exhaust machine employing a chassis and carrier, such as illustrated in U. S. Patent No. 2,637,144 issued May 5, 1953 to R. M. Gardner et al., entitled Automatic Lamp Stem Fabrication Apparatus and assigned to Sylvania Electric Products Inc., would provide greater production speeds. Such a carrier or conveyor would have generally parallel side portions and generally semi-cicular end portions and would provide the maximum number of Work stations and heads within the contines of a limited amount of oor space. However, to employ the conventional type rotary valve, mentioned above, with such a novel exhaust machine would entail the use of flexible sweeps between the upper rotary portion of said valve and the exhaust heads of the machine to compensate for the greater distance between said valve and its end portions of the exhaust machine, and the relatively shorter distances between said valve and the parallel straight side portions of said exhaust machine. Obviously, conventional rigid type vitreous sweeps could not be used in such a machine. Further, use of the plastic or rubber flexible connections would not provide a satisfactory seal, and would allow objectionable leakage of deleterious gases and air into either the lamp or the vacuum system itself of the exhaust machine.

Hence, it has been found advantageous according to the present invention to provide a straight line conveyor type exhaust machine and a novel valve arrangement for such an exhaust machine for the manufacture, desirably, of`incandescent lamps. The valve arrangement of the invention intermittently subjects the lamp to the vacuum system of the exhaust machine without causing any objectionable leakage or contamination either into the lamp or into the vacuum system. The valve arrangement may comprise a lower valve which is mechanicallyreciprocable up and down in a vertical directionhandl an upper (moving or indexing) valve provided with an intermediate chamber. This upper moving valve is a part of each` exhaust head of the exhaust machine. When the upper moving valve indexes into position in a particular station, the lower valve moves upwardly to meet the upper indexed valve. Both the upper and lower valves are provided with their own sealing plungers. The lower valve plunger opens as soon as the intermediate chamber of the upper moving valve is sealed by a sealing washer disposed about said lower plunger and before the upperl valve plunger or plug is open. This procedure permitsy the vacuum system to evacuate any minute amount of contamination from the intermediate chamber prior to the opening of the exhaust head to the vacuum system. On

disengagement of the upper and lower valves by down-` Referring now to the drawings in which like numerals of reference indicate similar parts throughout the several views:

Fig. 1 is a fragmentary horizontal sectional view of the conveyor and drive mechanism of a straight line conveyor type exhaust machine of the invention along the line I--I of Fig. 2 in the direction of the arrows.

Fig. 2 is a vertical sectional view of the straight linel conveyor type exhaust machine of Fig. 1 showing the novel exhaust valve arrangement of the invention and the means for reciprocating the lower valve along the line lI-II of Fig. l in the direction of the arrows.

Fig. 3 is an enlarged sectional view of the exhaust valve arrangement of the invention.

Fig. 4 is a further enlarged vertical sectional view of the upper indexing valve and the lower reciprocable valve.

Fig. 5 is a horizontal sectional view of the upper valve along the line V-V of Fig. 4 in the direction of the arrows.

Referring now to the drawings in detail a straight line conveyor type exhaust machine 1i) of the invention, onlyA one embodiment of which is illustrated, comprises a conveyor 12 provided with a plurality of heads 14 (Figs. 1

and 2) for supporting and transporting a series ofv electrical devices, such as incandescent lamps 16. The lamps 16 are exhausted by the machine 10. The conveyor 12I is indexable through a plurality of work stations on a frame 18 by an indexing mechanism 20.

Frame and conveyor The frame 18 of the present embodiment (Figs. l and 2) comprisesa table 22 which extends the length of the I exhaust machine 10 and may be in the form of a channel member with a web at the top and the flanges projecting downwardly. This table 22 is supported from the lloor by a plurality of legs 23 (Figs. 1 and 2). Upstanding from the table are a pluralityof pedestals, the end pedestal desirably in the form of -'a channel member 25 and the intermediate pedestals desirably in the form of spaced plates (not shown). All of the pedestals are united to an upper channel member 28 by the legs 23. The channel 4member 28 extends the length of the exhaust machine 10.

The conveyor 12 for carrying the incandescent lamps 16 in the heads 14 comprises a series of normally vertical channel members 29 (Figs. 1 and 2) for carrying rollersA 30 and v32 pivoted thereto. The upper rollers 30 travel .in a groove 33 in a track member 34, which is supported vby the legs 23. The other or lower rollers 32 ride in lPatinten Mani?, 1959 atcorrespondingr lower "groove 36 in a similar pedestal supported-track member-38.- This means that each channel member 29 is supportedto travel on the upper track member 34 and prevented from moving out of the upper groove 33 thereof by ai lower roller 32 riding in` the lowergroove 36 of the lower track member 38. These track members 34 and 38extend along the front and back of the exhaustmachine 10. At both ends of the exhaust machine the channel members 29 and theircarried lamps 16 are supported by the upper and lower chains 40 and 42 respectively. The lamps 16 may travel fromione end to the other along the front and tothe back ofthe exhaust machine 10. The lamps 16 may be-loaded atrStations l through 2, evacuated at Station 3 etc., tipped off for example at the next to the last stationand unloadedat the last station of the exhaust machine 10.

Each channel member 29 is also provided with an upper mount rod support 44 (Figs. 2 and 3) and a lower mount rod support 46 .for resiliently supporting, as hereinafter explained a head supporting mount rod or body 47.

Drive mechanism The driving means or indexing means (Figs. 1 and 2) for the conveyor 12 comprises a motor 52, (driving through reduction gearing 54) a chain 56 passing over a sprocket wheel 58. The sprocket wheel 58 is mounted one drive shaft 60 rotating on bearings 61 (Fig. 1) mounted on the table 22. This shaft 60 carries at one end a cam 62 in which rides a roller 64 on a lever 66. The lever 66 is pivoted at 70`to the frame 18 of the exhaust machine 19. The free end of the lever 66 is connected to a crank 76 by a link'72. The crank 76 is mounted on a vertical shaft 80 (Fig. l) carrying sprocket wheels 82 (Fig. 2) over which chains 40 and 42 pass and to which the series of channel members 29 are connected by means of angular clips 86 and 88 respectively (-Fig. 2). The chains 40 and 42 also pass around sprocket wheels (similar to wheels 82) on a shaft 84 (Fig. 2) at theother end of the frame 18. The angular clips 86 and 88 are connected at their upper ends by pivot pins 90 and 92.to the chains 40 and 42 respectively and are connected at their lower ends by bolts 94` and 96y to the series of channel members 29.

The shaft 80 (Fig. l) also carries a ratchet wheel 98 engaged by a pawl.100 and pivotally connected to the crank 76 whereby reciprocation of the link 72 at each revolution of the shaft 60 turns the shaft 80 sufliciently to move, through the above described chain mechanism, each .lamp supporting channel 29 from one station to the next. A pawl 104 pivoted to the table 22 and springbiased toward the ratchet 98 is provided to hold said ratchet 98 in a stationary position while the crank 76 is being returned preparatory to making the next indexing movement.

As shown particularly in Figs. 2 and 3, each upper mount rod support 44 and lower mount rod support 46 is provided with suitable bushings 106 for receiving therein (in reciprocable engagement therewith) the hollow mount rod 47. This mount rod `47 carries a head 14 on the 4upper end thereof and an indexable upper valve 110 of ;.avalve arrangement of the invention on the lower portion thereof. `It will be understood that each head 14 is provided with a valve 110.

Head

As shown particularly in Figs. 2 and 3, each of the heads 14 comprises a compression rubber assembly having a hollow body 112 threadably secured at its lower end to 1the;mount rod.47. The body 112 is provided with an upper threaded portion for carrying thereon a hollow cap 114. The'cap 114 has a suitable operating handle 116. A compression rubber'118 is seated in the body 112 betweenia washer119 and a hollow ballbearing insert 120. Thisfiinsert y120 is carried between the upper portions 'of the.` body 112andrthe cap 114; As shown in Fig. 3 an exhaust tubulation 122 of the lamp 16 may be inserted through the cap 114,-thel insert 120, the compression rubber 118 and washer 119 until it strikes a hollow tubulation stop 123. Rotation of the handle 116 compresses the rubber 118 about the lower end of the tubulation 122 of the incandescent lamp 16 and hermetically seals the tubulation 122 within the head 14.'

Mount rod supporting assembly Each of the mount vrods 47 is provided with a longitudinal keyway 124 adjacent the upper mount rod support 44 and into which a key'126 extends. The mount rod 47 also carries thereon an adjustable upper collar 128 and an adjustable lower collar or stop 130 (Fig. 3). A spring 132 which encircles the mount rod 47 between the upper mount rod support 44 and the upper collar 128 insures proper vertical positioning of a head 14 during index. The lower adjustable stopv 130 limits the downward travel of the mount rod`47. The primary function ofthe spring 132 is to compensate for the difference in theposition of eachindividual lower value 137 of' the exhaust valve arrangement when in the exhausting' position.

The vhollow mount rod 47 is provided with an axial ex haust hole 134which extends from the hollow'body 112 of the'head'14, (Figs. 3 and 4) to an'enlarged end portion 136 "on vthe lower threaded end thereof. This enlarged end portion 136 forms a part of each of thev upper valves 110 of the valve arrangement of the invention..

Exhaust valve In addition to the upper valve 110 each valve arrangement has a reciprocable lower valve 137. Each upper.

thehole in the seal washer 141 and an intermediate outer chamber 144.

Each of the lower valves 137 (Figs. 3 through 5) are mounted in a bar or housing 145 provided with a plurality of axial (partially threaded) holes or cavities 146 for.

securing the lower valve 137 and providing an exhaust system connecting chamber. A nipple 147 connects each of said holes 146 to a llexible line 148 of the vacuum system of the exhaust machine 10. As shown particularly in Fig. 2 the ilexible line 148 connects the nipple 147 to an exhaust manifold 149 of the vacuum system secured to the frame 18 of the exhaust machine l. The bar 145 is carried on the upper end of a pair of lower valve mount rods 150 (only one of which is shown in Figs. 1, 3 and 4), which rods 150are vertically reciprocable (Fig. 2)-in bearings 151 upstanding from the table 22.

It will be understood from a consideration of Figs. 3 and 4 that at the upper portion each of the cavities 146 in the bar 145 is threaded. A hollow lower plug 152 of T-shaped vertical section threadably engages the upper threaded portion of the hole 146, has a generally T-shaped v seal washer mounting lug 152 in its upper surface, and secures a resilient sealing washer 154 between the hollow plug 152 and the bar 145. An intermediate chamber sealing washer 156 is slip fitted (suitably axially) to the lug 152' on the upper' surface of the lower plug 152. The lower plug 152 is provided with an axial hole 157 having in downwardly depending succession: a lower plunger operating portion 158, an enlarged plunger head operating portion 160,A and a threaded still larger lower cap mounting portion 162. A hollow lower cap 164 is threadably secured inthe mounting portion 162 of the hole 157.

A'n inverted nail-like plunger 166 has its head secured" withmthe plunger head operating portion 160between-4 5. a resilient Washer 168 and a spring 170 and projects through the intermediate chamber sealing washer 156.

It will be understood from Figs. 3 and 4 that the lower portion of the spring 170 rests in a spring retaining hole p provided in the lower cap 164and'which is in registry with the plunger head operating portion 160 of the hole 157, in the lower plug 152. The lower cap 164 is also provided with a hole 174 for connecting each of the spring receiving apertures therein with the exhaust system connecting chamber portion of the holes 146 in the bar 145.

Valve operation The valve arrangement of the invention intermittently subjects the lamp 16 to the vacuum system manifold 149 (Fig. 2) of the exhaust machine 10 and eliminates objectional leakage of air or deleterious gases into the lamp 16 from the vacuum system manifold 149. When the upper (moving or indexable) valve 110 indexes into a particular station of the exhaust machine 10, the lower (vertically reciprocable) valve 137 moves upwardly to meet the now indexed upper valve 110. Desirably the lower spring 170 should be weaker than the upper spring 143 so that when (the lower plunger 166 strikes the upper plunger 142) the lower valve 137 opens as soon as the intermediate chamber 144 of the upper valve 110 is sealed by the sealing washer 156 and before the upper plunger 142 is moved upwardly and the upper valve 110 is opened. This permits the vacuum system manifold 149 of the exhaust machine to evacuate any small amounts of contamination from the intermediate chamber 144 and lower plunger hole 143 prior to the opening of an exhaust head 14 (through the upper valve 110) to the vacuum system manifold 149. When the lower valve 137 becomes disengaged from the upper valve 110, the springs 143 and 170 move the upper plunger 142 and the lower plunger 166 respectively into the closed position, thus automatically sealing both values 110 and 137.

The lower valve mount rods 150 are recprocable in the bearings 151 by means of a lower valve reciprocating mechanism 175.

Lower valve reciprocating mechanism As shown particularly in Figs. l and 2 the main shaft 60 carries a pair of lower valve reciprocating cams 180, only one of which is shown in Figs. l and 2. Each of the cams 180 engages a roller 182 on a pin 183 carried by a lever 184. The lever 184 is pivoted on a bracket 186 upstanding from the top of the table 22. Each of the levers 184 carries a yoke on its right hand end (when viewed in Fig. 2) for connection by means of a roller on a pin 185 to the lower valve section mount rod 150. The pin 185 reciprocates in a vertical slot in the bearing 151.

It will be understood from a consideration of Fig. 2 particularly that the lower valve 137 for the head 14 directly opposite the right hand head 14, as viewed in Fig. 2, is provided with a lever 188 pivoted on a bracket 186 and generally similar to the lever 184 except that the lever 188 is provided with a roller pin clearance slot 190. The lever 188 is secured by means of the slot 190 between the cam roller 182 and the lever 184. The lever 188 is connected to the rod 150 by the yoke and a roller on a pin 185, as hereinbefore described. It will be understood that the reciprocating mechanism 175 functions to simultaneously lift the mounting bars 145, with the lower valves 137 carried thereby into engagement with the registering upper valves 110.

It will be understood from a consideration of Fig. 2 that when the lower valve reciprocating cams ,180 are in the position shown in Fig. 2, that the upper valve 110 is in its uppermost or vacuum system pumping position. When the cams 180 are rotated 180 from the position shown in Fig. 2, the valves 110 will be in their lowermost position or indexing position.

Although a preferred embodiment ofthe invention has been' disclosed it will be understood that modifications may be made within the spirit and scope of the invention.

I claim: 1. An exhaust head for a straight-line conveyor-type machine for exhausting lamps, comprising a body, supporting and sealing means on said body for supporting a lamp during exhaust and hermetically sealing said lamp from the atmosphere, said body being provided with a `first passageway connecting said supporting and sealing source of vacuum to the atmosphere, a second valve in` said second passageway and adapted to hermetically seal said second passageway from the atmosphere, and reciprocating means for moving said housing toward said body and said second valve into engagement with said first valve thereby causing said second valve to open and permit the evacuation of said second passageway by said source of vacuum, said reciprocating means being further operable to cause further movement of said housing with respect to said body thereby causing said first valve to open and permitting the subsequent evacuation of said first passageway and said lamp by said source of vacuum.

2. An exhaust head for a straight-line conveyor-type machine for exhausting lamps, comprising a body, supporting and sealing means on said body for supporting a lamp during exhaust and hermetically sealing said lamp from the atmosphere, said body being provided with a first passageway connecting to said supporting and sealing means and the interior of said lamp, a first valve in said first passageway and adapted to hermetically seal said first passageway from the atmosphere, extension means on said body adapted to provide an intermediate chamber between said first passageway and the atmosphere, a housing disposed in registry with said body, a source of vacnum connected to said housing, said housing being provided with a second passageway connecting said source of vacuum to the atmosphere, a second valve in said second passageway and adapted to hermetically seal said second passageway from the atmosphere, and reciprocating means for moving said housing toward said extension means and said second valve into engagement with said first valve thereby causing said second valve to open and permit the evacuation of said intermediate chamber and said second passageway by said source of vacuum, said reciprocating means being further operable to cause further movement of said housing with respect to said extension means thereby causing said first valve to open and permitting the subsequent evacuation of said first passageway and said lamp by said source of vacuum.

3. An exhaust head for a straight-line conveyor-type machine for exhausting lamps, comprising a body, supporting and sealing means on said body for supporting a lamp during exhaust and hermetically sealing said lamp from the atmosphere, said body being provided with a first passageway connecting said supporting and sealing means and the interior of said lamp to the atmosphere and having a first seat, a first valve member in said first passageway and engageable with said first seat, a first resilient means associated with said first valve member to hermetically seat said first valve member in said first seat and seal said first passageway from the atmosphere, a housing disposed in registry with said body, a source of vacuum connected to said housing, said housing being provided with a second passageway connecting said source of vacuum to the atmosphere and having a second seat,

a second valve member in said second passageway and engageable with said second seat, a second resilient means associated with said second valve member to hermetically ,seat-said second valve member in said second 4seat and seal said second passageway from' the atmosphere, said secondresifient means beingpyieldingly weaker than said first resilient means, and reciprocating means for moving saidhousing toward said body and said second valve member into engagement with said first valve member thereby causing said second valve member to disengage from said second seat and permit the evacuation of said second passageway by said source of vacuum, said reciprocating means being further operable to cause further movement-of said housing with respect to said body thereby causing said first valve member to disengage from said first-seat and permitting the subsequent evacuation of said first passageway and said lamp by said source of vacuum.

4.Anl exhaust head for a straight-line conveyor-type machine for exhausting lamps, comprising a body, supporting and sealing means on said body for supporting a lamp during exhaust and hermetically sealing said lamp from the atmosphere, said body being provided with a first passageway connecting to said supporting andsealing means and the interior of said lamp and having a first seat, a first valve member in said first passagewayl and engageable with said first seat, a first resilient means associated with said first valve member to hermetically seat said first valve member in said first seat and seal said first passageway from-the atmosphere, extension means on said body adapted to provide an intermediate chamber between said first passageway and the atmosphere, a housing disposed in registry with said body, a source of vacuum connected to said housing, said housing being provided with a second passageway connecting said source of vacuum to the atmosphere and having a second seat, a second valve member in said second passageway and engageable with said second seat, a second resilient means associated with said second valve member to hermetically seat said second valve member in said second seat and seal said second passageway from the atmosphere, said second resilient means being yieldingly weaker than said first resilient means, and reciprocating means for moving said housing toward said extension means and said second valve member into engagement with said first valve member thereby causing said second valve member to disengage from said seco-nd seat and permit the evacuation of said intermediate chamber and said second passageway by said source of vacuum, said reciprocating means being further operable to cause further movement of said housing with respect to said extension means thereby causing said first valve member to disengage from said first seat and permitting the subsequent evacuation of said first passageway and` said lamp by said source of vacuum.

5. A straight-line conveyor type machine for exhausting lamps, comprising a frame, a conveyor indexable about said frame, a plurality of exhaust heads carried by said conveyor, each of said exhaust heads comprising a body, supporting and sealing means on said body for supporting a lamp during exhaust and hermetically sealing said lamp from the atmosphere, said body being provided with a first passageway connecting said supporting and sealing means and the interior of said lamp to the atmosphere, a first valve in said first passageway and adapted to hermetically seal said first passageway from the atmosphere, a housing reciprocable in said frame and disposed in registry with said body, a source of vacuum connected to said housing, said housing being provided with a second passageway connecting said source of vacuum to the atmosphere, a second valve in said second passageway and adapted to hermetically seal said second passageway from the atmosphere, and reciprocating means for moving said housing toward said body and said second valve into engagement with said first valve thereby causing said second valve to open and permit the evacuation of said second passageway by said source of vacuum, said reciprocating means being further operable to cause further movement of said housing with respect to said 8a body thereby causingv said first` valve to open and permitting the' subsequent evacuation of said first passageway andsaid lamp by said source of vacuum.

6. A straight-line conveyor type machine for exhausting lamps, comprising a frame, a conveyor indexable about said frame, a plurality of exhaust heads carried by said conveyor, each of said exhaust heads comprising a body, supporting and sealing means on said body for supporting a lamp during exhaust and hermetically sealing said lamp from the atmosphere, said body being provided with a first passageway connecting to said supporting and sealing means and the interior of said lamp, a first valve in said first passageway and adapted to hermetically seal said first passageway from the atmosphere, extension means on said body adapted to provide an intermediate chamber between said first passageway and the atmosphere, a housing reciprocable in said frame and disposed in registry withy said body, a source of vacuum connected to said housing, said housing being provided with a second passageway connecting said source of vacuum to the atmosphere, a second valve in said second passageway and] adapted to hermetically seal said second passageway from the atmosphere, and reciprocating means for moving said housing towardA said extension means and said second valve into engagement with said first valve thereby causing said second valve to open and permit the evacuation of said intermediate chamber and said second passageway by said source of vacuum, said reciprocating means being further operable to cause further movement of said housing` with' respect to said extension means thereby causing said first valve to open and permitting the subsequent evacuation of said first passageway and said lamp by said source of vacuum.

7. A'straight-line conveyor type machine for exhausting lamps, comprising a frame, a conveyor indexable about said frame, a plurality of exhaust heads carried by said conveyor, each of said exhaust heads comprising a body, supporting and sealing means on said body for supporting a lamp during exhaust and hermetically sealing said lamp from the atmosphere, said body being provided with a first passageway connecting said supporting and sealing means and the interior of said lamp to the atmosphere and having a first seat, a first valve member in said first passageway and engageable with said first seat, a first resilient means associated with said first valve member to hermetically seat said first valve member in saidfirst seat and seal said first passageway from the atmosphere, a housing disposed in registry with said body, a source of vacuum connected to said housing, said housing being provided with a second passageway connecting said source of vacuum to the atmosphere and having a second seat, a second valve member in said second passageway and engageable with said second seat, a second resilient means associated with said second valve member to hermetically seat said second valve member in said second seat and seal said second passageway from the atmosphere, said second resilient means being yieldingly weaker than said first resilient means, and reciprocating means for moving said housing toward said body and said second valve member into engagement with said first valve member thereby causing said second valve member to disengage from said second seat and permit the evacuation of said second passageway by said source of vacuum, said reciprocating means being further operable to causev further movement of said housing with respect to said body thereby causing said first valve member to disengage from said first seat and permitting the subsequent evacuation of said first passageway and said lamp by said source of vacuum.

8. A straight-line conveyor type machine for exhausting lamps, comprising a frame, a conveyor indexable about said` frame, a plurality of exhaust heads carried by said conveyor, each of said exhaust heads comprising a body, supporting and sealing means on said body for supporting a lamp during exhaust and hermetically sealing 9 said lamp from the atmosphere, said body being provided with a rst passageway connecting to said supporting and sealing means and the interior of said lamp and having a first seat, a first valve member in said first passageway and engageable with said first seat, a first resilient means associated with said rst valve member to hermetically seat said iirst valve member in said rst seat and seal said rst passageway from the atmosphere, extension means on said body adapted to provide an intermediate chamber between said rst passageway and the atmosphere, a housing disposed in registry with said body, a source of vacuum connected to said housing, said housing being provided with a second passageway connecting said source of vacuum to the atmosphere and having a second seat, a second valve member in said second passageway and engageable with said second seat, a second resilient means associated with said second valve member to hermetically seat said second valve member in said second seat and seal said second passageway from the atmos phere, said second resilient means being yieldingly weaker than said rst resilient means, and reciprocating means for moving said housing toward said extension means and said second valve member into engagement with said rst valve member thereby causing said second valve member to disengage from said second seat and permit the evacuation of said intermediate chamber and said second passageway by said source of vacuum, said reciprocating means being further operable to cause further movement of said housing with respect to said extension means thereby causing said first valve member to dsengage from said first seat and permitting the subsequent evacuation of said iirst passageway and said lamp by said source of vacuum.

References Cited in the le of this patent UNITED STATES PATENTS 1,322,559 Gethman Nov. 25, 1919 

